The present invention generally relates to semiconductor devices, and more particularly, to semiconductor devices embedded within contact lenses.
Contact lenses are widely used by the general population to correct and enhance visual perception. In addition, embedded electronic devices have been incorporated within contact lenses to monitor body chemistry. For example, through the use of sensors and integrated circuits embedded within a contact lens, glucose levels in the tears of a diabetic contact lens wearer may be determined.
Referring to FIG. 1, a cross-sectional diagram of a device 100A to be embedded within a contact lens, as known in the art, is illustrated. Device 100A contains one or more discrete components 101. The one or more discrete components 101 include a semiconductor device 102A having a sensor 104A, a radio-frequency identification (RFID) antenna 106A, and a processing circuit 108A. The one or more discrete components 101 are enclosed in individual packages and may, therefore, be electrically coupled together via a substrate 112 (i.e., a circuit board) using one or more solder connections 110. Solder connections 110 may be formed using a multitude of methods, such as the controlled collapse chip connection (C4) method. The mounting of discrete components 101 to substrate 112 may result in device 100A having a large size that requires device 100A to be embedded within a thicker contact lens. This in turn can lead to a decrease in wearer comfort. The large size of device 100A may also render device 100A visually perceptible to a contact lens wearer, such that the device 100A may at least partially obstruct the contact lens wearer's field of vision.
Furthermore, device 100A utilizes RFID and is therefore powered by the presence of a radio-frequency (RF) field being received by antenna 106A. The wearer of the contact lens is, therefore, subjected to in-bound RF radiation in order to retrieve data collected by device 100A through sensor 104A. This RF radiation may impair the contact lens wearer's health (e.g., burns to the eye, brain tumor).